First-Order System Least Squares Finite-Elements for Singularly Perturbed Reaction-Diffusion Equations

Autor: James H. Adler, Scott MacLachlan, Niall Madden
Rok vydání: 2020
Předmět:
Zdroj: Large-Scale Scientific Computing ISBN: 9783030410315
LSSC
DOI: 10.1007/978-3-030-41032-2_1
Popis: We propose a new first-order-system least squares (FOSLS) finite-element discretization for singularly perturbed reaction-diffusion equations. Solutions to such problems feature layer phenomena, and are ubiquitous in many areas of applied mathematics and modelling. There is a long history of the development of specialized numerical schemes for their accurate numerical approximation. We follow a well-established practice of employing a priori layer-adapted meshes, but with a novel finite-element method that yields a symmetric formulation while also inducing a so-called “balanced” norm. We prove continuity and coercivity of the FOSLS weak form, present a suitable piecewise uniform mesh, and report on the results of numerical experiments that demonstrate the accuracy and robustness of the method.
Databáze: OpenAIRE